6.28/1.80 NO 6.28/1.80 6.28/1.80 6.28/1.80 The system was reversed. 6.28/1.80 6.28/1.80 Remains to prove termination of the 3-rule system 6.28/1.80 { b a -> , 6.28/1.80 c a -> b c b c , 6.28/1.80 c b -> a a } 6.28/1.80 6.28/1.80 6.28/1.80 Loop of length 24 starting with a string of length 6 using right expansion 6.28/1.80 and the encoding {a=b, b=a, c=c}: 6.28/1.80 6.28/1.80 .cb.bbbb 6.28/1.80 rule cb -> acac at position 0 6.28/1.80 .acac.bbbb 6.28/1.80 rule cb -> acac at position 3 6.28/1.80 .acaacac.bbb 6.28/1.80 rule ca -> bb at position 4 6.28/1.80 .acaabbc.bbb 6.28/1.80 rule ab -> at position 3 6.28/1.80 .acabc.bbb 6.28/1.80 rule ab -> at position 2 6.28/1.80 .acc.bbb 6.28/1.80 rule cb -> acac at position 2 6.28/1.80 .acacac.bb 6.28/1.80 rule ca -> bb at position 3 6.28/1.80 .acabbc.bb 6.28/1.80 rule ab -> at position 2 6.28/1.80 .acbc.bb 6.28/1.80 rule cb -> acac at position 1 6.28/1.80 .aacacc.bb 6.28/1.80 rule cb -> acac at position 5 6.28/1.80 .aacacacac.b 6.28/1.80 rule ca -> bb at position 4 6.28/1.80 .aacabbcac.b 6.28/1.80 rule ab -> at position 3 6.28/1.80 .aacbcac.b 6.28/1.80 rule cb -> acac at position 2 6.28/1.80 .aaacaccac.b 6.28/1.80 rule ca -> bb at position 6 6.28/1.80 .aaacacbbc.b 6.28/1.80 rule cb -> acac at position 5 6.28/1.80 .aaacaacacbc.b 6.28/1.80 rule ca -> bb at position 6 6.28/1.80 .aaacaabbcbc.b 6.28/1.80 rule ab -> at position 5 6.28/1.80 .aaacabcbc.b 6.28/1.80 rule ab -> at position 4 6.28/1.80 .aaaccbc.b 6.28/1.80 rule cb -> acac at position 4 6.28/1.80 .aaacacacc.b 6.28/1.80 rule ca -> bb at position 5 6.28/1.80 .aaacabbcc.b 6.28/1.80 rule ab -> at position 4 6.28/1.80 .aaacbcc.b 6.28/1.80 rule cb -> acac at position 6 6.28/1.80 .aaacbcacac. 6.28/1.80 rule ca -> bb at position 5 6.28/1.80 .aaacbbbcac. 6.28/1.80 rule ca -> bb at position 7 6.28/1.80 .aaacbbbbbc. 6.28/1.85 EOF